1. Field of the Invention
The invention pertains to the field of power supply circuits. More particularly, the invention pertains to voltage adaptors for power supply modules which allow multiple modules with a lower AC voltage input requirement to be used with a higher AC voltage supply.
2. Description of Related Art
Very often it is required to deploy switch mode AC-DC power conversion assemblies powered from a 380V or 440V or 480V, three phase power system where no neutral connection is available. As typical switch mode power supply modules are designed to operate from a 208V or 220V or 230V or 240V power line, this is typically achieved by utilizing a power line frequency step down transformer that has to carry the entire rated power of the system. This entails uneconomical usage of space, excessive weight and increased cost.
While it is possible to specifically design AC-DC power supplies to work from a 380-440-480VAC power line, this generally requires a significant design effort that many times is beyond the economic scope of the program. A design technology that enables the use of preexisting power supply modules rated to 208-220-230-240VAC input without an excessively large, heavy and expensive step down transformer is warranted.